Theme |
The frontier of space medicine |
Title |
Mechanisms of gravity response and heat damage in C. elegans muscle cells |
Author |
Kenta Momma |
Department of Environmental Life Sciences, Graduate School of Life Sciences, Tohoku University |
Author |
Atsushi Higashitani |
Department of Environmental Life Sciences, Graduate School of Life Sciences, Tohoku University |
[ Summary ] |
Skeletal muscle wasting is a major obstacle for longterm space exploration. Similar to astronauts, the nematode Caenorhabditis elegans displays negative muscular and physical effects when subjected to microgravity in space. We found that in worms grown from the L1 larval stage to adulthood under microgravity, both gene and protein expression levels for muscular thick filaments, cytoskeletal elements, and mitochondrial metabolic enzymes decreased relative to parallel cultures on the 1-G centrifuge. In addition, TGF-β/DBL-1 signaling acts to alter body physique in response to environmental conditions including fluid dynamics. We also showed that elevated temperature increases cytosolic free Ca2+ concentration from RYR/UNC-68 leakage in vivo in the muscles of C. elegans. This subsequently leads to mitochondrial fragmentation and dysfunction, and breakdown of myofilaments similar to rhabdomyolysis. |